This invention relates to heterojunction devices, particularly those of the photovoltaic type useful in both absorption and emission modes of operation.
Research on semiconductor devices at optical wavelengths has indicated needs both for more efficient broadband detectors and for light-emitting diodes operating at wavelengths as yet not achieved with existing devices.
Moreover, the new awareness by research organizations of the opportunities presented by the so-called energy crisis for more modes of power conversion has stimulated a search for new solar cells.